How to Guide
112
Plastics Technical Manual
Hydronic Heating, Chilled 
Water or Geothermal 
Applications
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as hydronic, chilled water or geothermal heat pump systems, 
careful consideration of piping material characteristics and 
system requirements must be made. This includes taking 
into account pressure, temperature, flow velocity, design 
stresses, environmental factors and the chemical resistance 
of the piping materials to the fluids (heat-transfer fluids, 
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these characteristics and system requirements in order 
to select the correct piping product for the particular 
application. The table below highlights some of the key 
points to consider when designing or installing these types 
of systems.
This manual is not a complete engineering reference 
addressing all aspects of design and installation of these 
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Association: www.igshpa.okstate.edu or The GEO Exchange 
at www.geoexchange.org.
“DOs” for all hydronic applications
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IPS P-70 or Oatey Industrial Grade primers.
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cements.
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installation instructions.
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the boiler is less than the temperature and pressure rating 
of the pipe (see charts below).
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the applicable operating temperature.
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installing plumbing and heating equipment.
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and contraction as recommended in the Charlotte Pipe and 
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installing FlowGuard Gold systems.
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Do not bend or pull pipe into position after being solvent 
welded.
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brass transition or other metallic components to support 
the weight of the metal system.
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prevent cross-connections between hot and cold water lines.
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condenser coils thoroughly with mild ionic detergent solution 
to remove incompatible oils prior to piping installation.
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flushing.
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in the hydronic radiant heating system are compatible with 
CPVC.
“DON’Ts” for all hydronic applications
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pressure of the piping system.
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molded threads for FlowGuard Gold systems.
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components.
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heating applications.
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become discolored or has gelled.
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SPECIAL CONSIDERATIONS
Prior to installing PVC or CPVC piping in hydronic 
applications, it is important to flush the interior of the heat 
exchangers and the exterior of the condenser coils 
thoroughly with a mild ionic detergent solution to remove 
incompatible oils. Failing to do so could result in system 
failure and property damage.
Verify that all boiler cleaning and sealing chemicals used in 
hydronic radiant heating systems are compatible with PVC 
or CPVC. Failure to do so could result in system failure and 
property damage.
Equipment leaks in refrigeration or HVAC systems may 
release POE oils or other contaminants into the piping 
system. These oils and contaminants are incompatible with 
PVC or CPVC and such exposure may result in pipe or 
fitting failure regardless of flushing.










